Ubuntu Karmic Koala Alpha is being developed and will be released as Ubuntu 9.10 in October. If you want to play around with Karmic Alpha on Amazon EC2, I have published new AMIs in the US and EU regions for 32- and 64-bit:
A Karmic desktop image for EC2 is also available if you wish to monitor progress in that area.
Warning! Karmic is an unstable alpha developer version and is not intended for use in anything resembling a production environment.
Please note that we are still defaulting to Amazon’s 2.6.21fc8 kernel which, though functional and stable, is getting older and older for each new release of Ubuntu. One effect of this is that AppArmor will not be enabled, though this should not affect the functionality of any software.